Pine needle abortion in cattle: a review and report of 1973-1984 research   总被引：1，自引：0，他引：1  

L F James  R E Short  K E Panter  R J Molyneux  L D Stuart  R A Bellows 《The Cornell veterinarian》1989,79(1):39-52

Research has verified field observations that cows grazing ponderosa pine needles may abort. The incidence and nature of the abortions produced experimentally simulate very closely those reported by livestock producers and veterinarians. The incidence of experimentally-produced abortions varied markedly from year to year even though the needles were collected in the same general area each year. This suggests that the abortifacient compound(s) in the needles vary from year to year, probably due to environmental and site conditions. The impact of stress (cold and nutrition) as a factor in the abortions was examined. It was concluded that the only effects would be on the willingness of cows to eat the needles. The pine needle abortion problem, what is known of the etiology, and mechanisms of the abortion are reviewed. The usefulness of bioassay systems to study pine needle abortions is discussed.  相似文献   

Effects of induced parturition and early obstetrical assistance in beef cattle     

R A Bellows  R E Short  R B Staigmiller  W L Milmine 《Journal of animal science》1988,66(5):1073-1080

Pregnant crossbred beef females (33 second-calf cows and 73 primiparous heifers) bred to a single Hereford sire were assigned to a 2(3) factorial study involving age of dam, natural (NP) or induced (IP) parturition and late emergency (LA) or forced early (EA) obstetrical assistance. Parturition was induced with 10 mg flumethazone given i.m. between 1400 and 1600 on d 272 of gestation; EA was given when the cervix and birth canal were fully dilated. Average IP occurred 39.6 h postinjection, and 95.3% of the treated dams responded within 60 h postinjection; gestation was shortened 2.9 d (P approximately equal to .07). Dystocia score (from 1 = no assist to 4 = major traction required and 5 = abnormal presentation) was 1.12 vs 2.40 for LA and EA, respectively (P less than .01), and 11% of LA vs 84% of EA were assisted. Calf vigor score (1 = normal to 3 = severely depressed or dying) at birth was 1.3 for NP and 1.1 for IP (P approximately equal to .06) and 1.3 for EA and 1.1 for LA (P less than .05). This effect of EA was due to reduced vigor of calves experiencing abnormal presentation. Birth weights (BW) and weaning weights (WW) of calves from cows exceeded those from heifers (32.6 vs 30.8 kg, P less than .05; 210.9 vs 156.3 kg, P less than .01, respectively). Differences due to IP and EA in BW, WW, postpartum interval and conception rate were not significant, but weight gain of calves from EA dams tended (P approximately equal to .09) to be greater than weight gain of calves from LA dams.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

Calving rates in a tropical beef herd after treatment with a synthetic progestagen, norgestomet, or a prostaglandin analogue, cloprostenol     

JE FRISCH  CJ O'NEILL 《Australian veterinary journal》1996,73(3):98-102

Maiden heifers and lactating cows of known ovarian status and of several breeds were treated with a synthetic prostaglandin, cloprostenol, or a synthetic progestagen, norgestomet, at the start of an artificial insemination (AI) program. Animals in the cloprostenol treatment received 2 injections 10 days apart. Over the next 26 days those animals that showed oestrous behaviour were inseminated. Synchronisation rates and calving rates to insemination over the first 7 days were calculated. Those in the norgestomet treatment received an implant of norgestomet plus an injection of norgestomet and oestradiol valerate. The implant was removed 10 days later and the animals were given an injection of pregnant mare serum gonadotrophin (PMSG). They were inseminated at 48 h (maiden heifers) or 56 h (lactating cows) after implant removal. Calving rates to fixed-time insemination were recorded. After completion of the AI program the animals in both treatments were joined with bulls. Overall calving rates (AI plus bulls) were calculated. By day 7 of the program, 82% of the maiden heifers and 76% of the lactating cows in the cloprostenol treatment had been detected in oestrus. By day 21 the respective figures were 99% and 81% Norgestomet treatment had an immediate and a prolonged effect on ovarian activity in those females classified as having inactive ovaries at the start of the AI program. Calving rates of those females to fixed-time AI and overall were similar to those of the females with active ovaries in both treatments. Their calving rates to fixed-time insemination, and overall calving rates for the lactating females, were significantly higher than the corresponding values of their contemporaries treated with cloprostenol and inseminated on observed oestrus over 7 days. For those females classified as having active ovaries at the start of the AI program, calving rates to first insemination and overall were similar for both treatments. Overall calving rates of lactating cows of each breed were, with one exception, higher in the norgestomet treatment than in the cloprostenol treatment. Although norgestomet treatment was more expensive than cloprostenol treatment, the advantage in calf crop resulted in an overall monetary advantage to the norgestomet treatment.  相似文献   

The effect of artificial photoperiod at the end of the breeding season on plasma testosterone concentrations in stallions     

JE COX  PH REDHEAD†  NMA JAWADS‡ 《Australian veterinary journal》1988,65(8):239-241

Testosterone concentrations in stallions showed a seasonal trend with peak concentrations in the spring (April and May in Britain) and lowest concentrations in the period from December to February. The effect on this pattern of changing the length of the photoperiod at the end of the normal breeding season (mid-summer's day) was studied in 2 experiments. In the first experiment artificial illumination was organised from 21 June to mimic the effect of transfer to a southern hemisphere spring and summer, that is short days becoming longer. The stallions had low concentrations of testosterone in February and high concentrations in April. Concentrations in July, August and September were extremely low with a return to high values in late November/early December. In the second experiment, illumination was maintained at the equivalent of a 16 1/2-hour day from 21 June to mid December. These stallions had high testosterone concentrations in April, after which they fell until August, later rising to a maximum in October. These results are discussed in relation to transfer of stallions between the northern and southern hemispheres.  相似文献   

Aetiology and Endocrinology of Pseudopregnancy in the Goat     

MAM Taverne  JW Hesselink    MM Bevers  HA van  Oord JE Kornalijnslijper 《Reproduction in domestic animals》1995,30(4):228-230

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Effect of nutrition on response to exogenous FSH in beef cattle     

R B Staigmiller  R E Short  R A Bellows  J B Carr 《Journal of animal science》1979,48(5):1182-1190

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AAHA dental care guidelines for dogs and cats     

Holmstrom SE  Bellows J  Colmery B  Conway ML  Knutson K  Vitoux J;AAHA 《Journal of the American Animal Hospital Association》2005,41(5):277-283

The purpose of this document is to provide guidelines for the practice of companion animal dentistry for the veterinary profession. Dental care is necessary to provide optimum health and quality of life. Diseases of the oral cavity, if left untreated, are often painful and can contribute to other local or systemic diseases. This paper includes guidelines for materials and equipment, dental cleaning and evaluation, client communication, and pet home care.  相似文献   

The potential for dietary polyunsaturated fatty acids in domestic animals     

JE BAUER 《Australian veterinary journal》1994,71(10):342-345

SUMMARY The metabolism and clinical potential for dietary polyunsaturated fatty acids (PUFAs) modifications using oil supplements containing n-3 and n-6 fatty acids are reviewed. Their use in such disorders as renal disease, inflammatory and immune-related disorders, and dermatological conditions in dogs and cats is discussed. The influence of n-3 fatty acid-rich rations on the endotoxin response in horses is described. Progress has been made toward understanding the clinical potential for PUFAs in these species. However, they have not yet been shown to be efficacious in any of the conditions investigated.  相似文献   

Pituitary potency and ovarian activity in rats on two levels of dietary energy     

R A Bellows  R K Meyer  W G Hoekstra  L E Casida 《Journal of animal science》1966,25(2):381-385

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Hemodynamic effects of sevoflurane in spontaneously breathing cats     

BH  Pypendop  JE Ilkiw  JA Bolich 《Veterinary anaesthesia and analgesia》2003,30(2):105-106

Sevoflurane has recently been introduced in feline anesthesia. However, its cardiovascular effects have not, to our knowledge, been reported in this species. Six healthy cats, aged 1.81 ± 0.31 years (mean ± SEM) and weighing 3.47 ± 0.11 kg, were studied. Anesthesia was induced and maintained with sevoflurane in oxygen. Body temperature was maintained between 38.5 and 39.55 °C. After instrumentation, end‐tidal sevoflurane concentration was randomly set at 1.25, 1.5, and 1.75 times the individual minimum alveolar concentration (MAC), determined in a previous study, according to a Latin Square Design. Thirty minutes of stabilization was allowed after each change of concentration. ECG and heart rate, systemic and pulmonary arterial pressures, central venous pressure (CVP), and core body temperature were continuously monitored and recorded. Inspired and end‐tidal oxygen, carbon dioxide, and sevoflurane concentrations were measured using a Raman spectrometer, calibrated every 80 minutes with three calibration gases of known sevoflurane concentration (1, 2, and 5%). Moreover, at selected times, pulmonary artery occlusion pressure and cardiac output (thermodilution) were measured, and arterial and mixed venous blood samples were collected for pH and blood gas analysis, hemoglobin concentration, hemoglobin oxygen saturation, packed cell volume (PCV) and total protein determination, and lactate concentration measurement. Cardiac index (CI), stroke index (SI), systemic and pulmonary vascular resistance indices, rate‐pressure product, left and right ventricular stroke work indices (LVSWI and RVSWI, respectively), arterial and mixed venous oxygen contents, oxygen delivery, oxygen consumption, and oxygen utilization ratio were calculated. Data were analyzed by a Repeated Measure Latin Square Design followed by a Tukey's test for 2 × 2 comparisons. Arterial pH significantly decreased from 7.40 ± 0.05 to 7.29 ± 0.07 with the administration of increasing concentrations of sevoflurane. Similarly, LVSWI decreased from 3.72 ± 0.60 to 2.60 ± 0.46 g m^?2. Mean arterial pressure, PaO₂, mixed venous pH, CI, SI, and oxygen delivery tended to decrease dose‐dependently, whereas CVP, PaCO₂, Pv CO₂, PCV, and arterial and mixed venous hemoglobin concentrations tended to increase dose‐dependently with the administration of sevoflurane. However, these trends did not reach statistical significance, possibly because of the limited number of animals studied. Sevoflurane seemed to induce dose‐dependent cardiovascular depression in cats.  相似文献